1. Field of the Invention
The present invention relates to a magnetic disk apparatus which can realize higher recording density of a magnetic disk without requiring a large scale modification of hardware of the magnetic disk apparatus of the related art.
2. Description of the Related Art
FIG. 3 is a diagram for explaining a method of recording and reproducing data of a magnetic disk apparatus of the related art.
In the magnetic disk apparatus illustrated in FIG. 3, a timing signal recorded together with a servo signal for tracking is read to a hard disk or flexible disk and data sector pulses a, b are generated on the basis of this timing signal. In the writing operation, recording is performed in such a manner that one data sector R is stored to an area 10 between the data sector pulses a and b. On the occasion of writing the data, writing control of data sector R is conducted with reference to the data sector pulse a in the disk controller (control means) provided within the magnetic disk apparatus. In usual, one data sector F is recorded next to one data sector pulse a.
The data sector R is formed of the areas of sync field (Sync) 11, address mark (AM) 12, data (DATA) 13 and error correction code (ECC) 14 in a row.
In the readout operation, the sync field 11 is synchronized to the target data sector R, the address mark 12 is detected, data in the area of the subsequent data (DATA) 13 is read and error correction is made to the data read by the error correction code (ECC) 14.
However, in the magnetic disk apparatus of the related art described above, it has been difficult to increase the capacity of the data to be recorded because only one data section can be recorded for one data sector pulse.
Usually, an interval between the data sector pulses a and b must be narrowed to increase the capacity of data to be recorded to a magnetic disk by raising the recording density. The timing for generating the data sector pulse therefore must be changed for such purpose and thereby raises a problem that specification of interface and hardware must be changed.
Moreover, capacity of one data sector is limited depending on the specification of the interface. Only the data of limited capacity therefore can be input to one data sector even when the recording frequency of data for the magnetic disk is increased.